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Flask-RESTful 是一个 Flask 扩展，它添加了快速构建 REST APIs 的支持。它当然也是一个能够跟你现有的ORM/库协同工作的轻量级的扩展。Flask-RESTful 鼓励以最小设置的最佳实践。如果你熟悉 Flask 的话，Flask-RESTful 应该很容易上手。 关于flask的使用，参考我的之前的博客：https://blog.csdn.net/shifengboy/article/details/114274271 flask-restful官方文档：https://flask-restful.readthedocs.io/en/lates 中文文档：http://www.pythondoc.com/Flask-RESTful/ flask-restful 安装 pip install flask-restful flask-restful使用简单上手 from flask import Flask from flask_restful import Resource, Api app = Flask(__name__) api = Api(app) class HelloWorld(Resource): def get(self): return {'hello': 'world'} api.add_resource(HelloWorld, '/') if __name__ == '__main__': app.run(debug=True)运行结果： $ curl http://127.0.0.1:5000/ {"hello": "world"} Resourceful 路由Flask-RESTful 提供的主要构建块是资源。资源构建在 Flask 可插入视图之上，只需在资源上定义方法，就可以轻松访问多个 HTTP 方法。一个 todo 应用程序的基本 CRUD 资源是这样的: from flask import Flask, request from flask_restful import Resource, Api app = Flask(__name__) api = Api(app) todos = {} class TodoSimple(Resource): def get(self, todo_id): return {todo_id: todos[todo_id]} def put(self, todo_id): todos[todo_id] = request.form['data'] return {todo_id: todos[todo_id]} api.add_resource(TodoSimple, '/') if __name__ == '__main__': app.run(debug=True)运行结果： chenshifengdeMacBook-Pro:~ chenshifeng$ curl http://localhost:5000/todo1 -d "data=Remember the milk" -X PUT { "todo1": "Remember the milk" } chenshifengdeMacBook-Pro:~ chenshifeng$ curl http://localhost:5000/todo1 { "todo1": "Remember the milk" } chenshifengdeMacBook-Pro:~ chenshifeng$ curl http://localhost:5000/todo2 -d "data=Change my brakepads" -X PUT { "todo2": "Change my brakepads" } chenshifengdeMacBook-Pro:~ chenshifeng$ curl http://localhost:5000/todo2 { "todo2": "Change my brakepads" } chenshifengdeMacBook-Pro:~ chenshifeng$Restful 能够从 view 方法中理解多种返回值。类似于 Flask，你可以返回任何可迭代的并且它将被转换成一个响应，包括原始 Flask 响应对象。还支持使用多个返回值设置响应代码和响应头，如下所示: #!/usr/bin/python # -*- coding: UTF-8 -*- """ @author:chenshifeng @file:flask_restful_demo.py @time:2021/03/05 """ from flask import Flask, request from flask_restful import Resource, Api app = Flask(__name__) api = Api(app) class Todo1(Resource): def get(self): # Default to 200 OK return {'task': 'Hello world'} class Todo2(Resource): def get(self): # Set the response code to 201 return {'task': 'Hello world'}, 201 class Todo3(Resource): def get(self): # Set the response code to 201 and return custom headers return {'task': 'Hello world'}, 201, {'Etag': 'some-opaque-string'} api.add_resource(Todo1,'/todo1') api.add_resource(Todo2,'/todo2') api.add_resource(Todo3,'/todo3') if __name__ == '__main__': app.run(debug=True)运行结果： chenshifengdeMacBook-Pro:~ chenshifeng$ curl -i http://127.0.0.1:5000/todo1 HTTP/1.0 200 OK Content-Type: application/json Content-Length: 30 Server: Werkzeug/1.0.1 Python/3.9.2 Date: Fri, 05 Mar 2021 16:08:28 GMT { "task": "Hello world" } chenshifengdeMacBook-Pro:~ chenshifeng$ curl -i http://127.0.0.1:5000/todo2 HTTP/1.0 201 CREATED Content-Type: application/json Content-Length: 30 Server: Werkzeug/1.0.1 Python/3.9.2 Date: Fri, 05 Mar 2021 16:08:32 GMT { "task": "Hello world" } chenshifengdeMacBook-Pro:~ chenshifeng$ curl -i http://127.0.0.1:5000/todo3 HTTP/1.0 201 CREATED Content-Type: application/json Content-Length: 30 Etag: some-opaque-string Server: Werkzeug/1.0.1 Python/3.9.2 Date: Fri, 05 Mar 2021 16:08:34 GMT { "task": "Hello world" } chenshifengdeMacBook-Pro:~ chenshifeng$ Endpoints 端点很多时候，在一个 API 中，你的资源会有多个 url。可以将多个 url 传递给 Api 对象上的 add _ resource ()方法。每一个都将被路由到Resource api.add_resource(HelloWorld, '/', '/hello')您还可以将路径的某些部分作为变量匹配到Resource。 api.add_resource(Todo, '/todo/', endpoint='todo_ep')演示代码： from flask import Flask from flask_restful import Resource, Api app = Flask(__name__) api = Api(app) class HelloWorld(Resource): def get(self): return {'hello': 'world'} class Todo(Resource): def get(self, todo_id): # Default to 200 OK return {'task': 'Hello world'} api.add_resource(HelloWorld, '/', '/hello') api.add_resource(Todo, '/todo/', endpoint='todo_ep') if __name__ == '__main__': app.run(debug=True)演示结果： chenshifengdeMacBook-Pro:~ chenshifeng$ curl http://127.0.0.1:5000/ { "hello": "world" } chenshifengdeMacBook-Pro:~ chenshifeng$ curl http://127.0.0.1:5000/hello { "hello": "world" } chenshifengdeMacBook-Pro:~ chenshifeng$ curl http://127.0.0.1:5000/todo/1 { "task": "Hello world" } chenshifengdeMacBook-Pro:~ chenshifeng$ curl http://127.0.0.1:5000/todo/2 { "task": "Hello world" } 参数解析虽然 Flask 可以方便地访问请求数据(即 querystring 或 POST 表单编码的数据) ，但验证表单数据仍然是一件痛苦的事情。使用类似于 argparse 的库对请求数据验证提供内置支持。 from flask import Flask from flask_restful import reqparse, Api, Resource app = Flask(__name__) api = Api(app) parser = reqparse.RequestParser() parser.add_argument('rate', type=int, help='Rate to charge for this resource') class Todo(Resource): def post(self): args = parser.parse_args() print(args) # Default to 200 OK return {'task': 'Hello world'} api.add_resource(Todo,'/todos' ) if __name__ == '__main__': app.run(debug=True) chenshifengdeMacBook-Pro:~ chenshifeng$ curl -d 'rate=100' http://127.0.0.1:5000/todos { "task": "Hello world" } chenshifengdeMacBook-Pro:~ chenshifeng$ curl -d 'rate=foo' http://127.0.0.1:5000/todos { "message": { "rate": "Rate to charge for this resource" } }与 argparse 模块不同，reqparse. RequestParser.parse _ args ()返回 Python 字典，而不是自定义数据结构。 输入模块提供了许多常用的转换函数，例如 inputs.date ()和 inputs.url ()。 使用 strict = True 调用 parse _ args 可以确保在请求包含您的解析器没有定义的参数时抛出错误。 args = parser.parse_args(strict=True) $ curl -d 'rate2=foo' http://127.0.0.1:5000/todos { "message": "Unknown arguments: rate2" } 数据格式化默认情况下，在你的返回迭代中所有字段将会原样呈现。尽管当你刚刚处理 Python 数据结构的时候，觉得这是一个伟大的工作，但是当实际处理它们的时候，会觉得十分沮丧和枯燥。为了解决这个问题，Flask-RESTful 提供了 fields 模块和 marshal_with() 装饰器。类似 Django ORM 和 WTForm，你可以使用 fields 模块来在你的响应中格式化结构。 from flask import Flask from flask_restful import fields, marshal_with, Resource, Api app = Flask(__name__) api = Api(app) resource_fields = { 'task': fields.String, 'uri': fields.Url('todo') } class TodoDao(object): def __init__(self, todo_id, task): self.todo_id = todo_id self.task = task # This field will not be sent in the response self.status = 'active' class Todo(Resource): @marshal_with(resource_fields) def get(self, **kwargs): return TodoDao(todo_id='my_todo', task='Remember the milk') api.add_resource(Todo,'/todo') if __name__ == '__main__': app.run(debug=True)上面的例子接受一个 python 对象并准备将其序列化。marshal_with() 装饰器将会应用到由 resource_fields 描述的转换。从对象中提取的唯一字段是 task。fields.Url 域是一个特殊的域，它接受端点（endpoint）名称作为参数并且在响应中为该端点生成一个 URL。许多你需要的字段类型都已经包含在内。请参阅 fields 指南获取一个完整的列表。 $ curl http://127.0.0.1:5000/todo { "task": "Remember the milk", "uri": "/todo" } 完整例子 from flask import Flask from flask_restful import reqparse, abort, Api, Resource app = Flask(__name__) api = Api(app) TODOS = { 'todo1': {'task': 'build an API'}, 'todo2': {'task': '?????'}, 'todo3': {'task': 'profit!'}, } def abort_if_todo_doesnt_exist(todo_id): if todo_id not in TODOS: abort(404, message="Todo {} doesn't exist".format(todo_id)) parser = reqparse.RequestParser() parser.add_argument('task') # Todo # shows a single todo item and lets you delete a todo item class Todo(Resource): def get(self, todo_id): abort_if_todo_doesnt_exist(todo_id) return TODOS[todo_id] def delete(self, todo_id): abort_if_todo_doesnt_exist(todo_id) del TODOS[todo_id] return '', 204 def put(self, todo_id): args = parser.parse_args() task = {'task': args['task']} TODOS[todo_id] = task return task, 201 # TodoList # shows a list of all todos, and lets you POST to add new tasks class TodoList(Resource): def get(self): return TODOS def post(self): args = parser.parse_args() todo_id = int(max(TODOS.keys()).lstrip('todo')) + 1 todo_id = 'todo%i' % todo_id TODOS[todo_id] = {'task': args['task']} return TODOS[todo_id], 201 ## ## Actually setup the Api resource routing here ## api.add_resource(TodoList, '/todos') api.add_resource(Todo, '/todos/') if __name__ == '__main__': app.run(debug=True)获取列表 $ curl http://localhost:5000/todos { "todo1": { "task": "build an API" }, "todo2": { "task": "?????" }, "todo3": { "task": "profit!" } }获取一个单独的任务 $ curl http://localhost:5000/todos/todo3 { "task": "profit!" }删除一个任务 $ curl http://localhost:5000/todos/todo2 -X DELETE -v * Trying ::1... * TCP_NODELAY set * Connection failed * connect to ::1 port 5000 failed: Connection refused * Trying 127.0.0.1... * TCP_NODELAY set * Connected to localhost (127.0.0.1) port 5000 (#0) > DELETE /todos/todo2 HTTP/1.1 > Host: localhost:5000 > User-Agent: curl/7.64.1 > Accept: */* > * HTTP 1.0, assume close after body < HTTP/1.0 204 NO CONTENT < Content-Type: application/json < Server: Werkzeug/1.0.1 Python/3.9.2 < Date: Sat, 06 Mar 2021 03:29:33 GMT < * Closing connection 0增加一个新的任务 $ curl http://localhost:5000/todos -d "task=something new" -X POST -v Note: Unnecessary use of -X or --request, POST is already inferred. * Trying ::1... * TCP_NODELAY set * Connection failed * connect to ::1 port 5000 failed: Connection refused * Trying 127.0.0.1... * TCP_NODELAY set * Connected to localhost (127.0.0.1) port 5000 (#0) > POST /todos HTTP/1.1 > Host: localhost:5000 > User-Agent: curl/7.64.1 > Accept: */* > Content-Length: 18 > Content-Type: application/x-www-form-urlencoded > * upload completely sent off: 18 out of 18 bytes * HTTP 1.0, assume close after body < HTTP/1.0 201 CREATED < Content-Type: application/json < Content-Length: 32 < Server: Werkzeug/1.0.1 Python/3.9.2 < Date: Sat, 06 Mar 2021 03:31:02 GMT < { "task": "something new" } * Closing connection 0更新一个任务 $ curl http://localhost:5000/todos/todo3 -d "task=something different" -X PUT -v * Trying ::1... * TCP_NODELAY set * Connection failed * connect to ::1 port 5000 failed: Connection refused * Trying 127.0.0.1... * TCP_NODELAY set * Connected to localhost (127.0.0.1) port 5000 (#0) > PUT /todos/todo3 HTTP/1.1 > Host: localhost:5000 > User-Agent: curl/7.64.1 > Accept: */* > Content-Length: 24 > Content-Type: application/x-www-form-urlencoded > * upload completely sent off: 24 out of 24 bytes * HTTP 1.0, assume close after body < HTTP/1.0 201 CREATED < Content-Type: application/json < Content-Length: 38 < Server: Werkzeug/1.0.1 Python/3.9.2 < Date: Sat, 06 Mar 2021 03:32:44 GMT < { "task": "something different" } * Closing connection 0获取最新列表 $ curl http://localhost:5000/todos { "todo1": { "task": "build an API" }, "todo3": { "task": "something different" }, "todo4": { "task": "something new" } } |
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